Sample code for 30+ languages & platforms
Xbase++ Requires Chilkat v11.0.0+

Verify a .p7m and get Algorithm Information

See more Digital Signatures Examples

Demonstrates how to verify a .p7m and then examine the algorithms used by the signature.

Chilkat Xbase++ Downloads

Xbase++
LOCAL nSuccess
LOCAL oCrypt
LOCAL cInFile
LOCAL cOutFile
LOCAL oJson
LOCAL i
LOCAL nCount_i
LOCAL cStrVal
LOCAL cCertSerialNumber
LOCAL cCertIssuerCN
LOCAL cCertIssuerDN
LOCAL cCertDigestAlgOid
LOCAL cCertDigestAlgName
LOCAL cContentType
LOCAL cSigningTime
LOCAL cMessageDigest
LOCAL cSigningAlgOid
LOCAL cSignerDigest
LOCAL j
LOCAL nCount_j
LOCAL cOid
LOCAL cOidName
LOCAL cDer

nSuccess := 0

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

oCrypt := CreateObject("Chilkat.Crypt2")

cInFile := "qa_data/p7m/brainpoolP256r1.p7m"
cOutFile := "qa_output/something.dat"

//  Verify and extract the signed data.
nSuccess := oCrypt:VerifyP7M(cInFile, cOutFile)
IF (nSuccess == 0)
    ? oCrypt:LastErrorText
    oCrypt:destroy()
    RETURN
ENDIF

//  Examine details about the signature(s)
oJson := CreateObject("Chilkat.JsonObject")
oCrypt:GetLastJsonData(oJson)
oJson:EmitCompact := 0
? oJson:Emit()

//  Sample output

//  {
//    "pkcs7": {
//      "verify": {
//        "digestAlgorithms": [
//          "sha256"
//        ],
//        "signerInfo": [
//          {
//            "cert": {
//              "serialNumber": "FFFFE552B302FFFFFF1E34C3ACEB2FFFF",
//              "issuerCN": "The common name of the cert...",
//              "issuerDN": "",
//              "digestAlgOid": "2.16.840.1.101.3.4.2.1",
//              "digestAlgName": "SHA256"
//            },
//            "contentType": "1.2.840.113549.1.7.1",
//            "signingTime": "190409140500Z",
//            "messageDigest": "lQe9If7vZKFf/NlSYu5Esmlw3phVK/RFsbbb1uH73t8=",
//            "signingAlgOid": "1.2.840.10045.4.3.2",
//            "signerDigest": "lQe9If7vZKFf/NlSYu5Esmlw3phVK/RFsbbb1uH73t8=",
//            "authAttr": [
//              {
//                "oid": "1.2.840.113549.1.9.3",
//                "oidName": "contentType"
//              },
//              {
//                "oid": "1.2.840.113549.1.9.5",
//                "oidName": "signingTime"
//              },
//              {
//                "oid": "1.2.840.113549.1.9.52",
//                "oidName": "1.2.840.113549.1.9.52",
//                "der": "MBs ... AwI="
//              },
//              {
//                "oid": "1.2.840.113549.1.9.4",
//                "oidName": "messageDigest"
//              },
//              {
//                "oid": "1.2.840.113549.1.9.16.2.47",
//                "oidName": "signingCertificateV2",
//                "der": "MCYw .. 7PlQ=="
//              },
//              {
//                "oid": "1.2.840.113549.1.9.20",
//                "oidName": "1.2.840.113549.1.9.20"
//              }
//            ]
//          }
//        ]
//      }
//    }
//  }

//  Code for parsing the above JSON...

i := 0
nCount_i := oJson:SizeOfArray("pkcs7.verify.digestAlgorithms")
DO WHILE i < nCount_i
    oJson:I := i
    cStrVal := oJson:StringOf("pkcs7.verify.digestAlgorithms[i]")
    i := i + 1
ENDDO
i := 0
nCount_i := oJson:SizeOfArray("pkcs7.verify.signerInfo")
DO WHILE i < nCount_i
    oJson:I := i
    cCertSerialNumber := oJson:StringOf("pkcs7.verify.signerInfo[i].cert.serialNumber")
    cCertIssuerCN := oJson:StringOf("pkcs7.verify.signerInfo[i].cert.issuerCN")
    cCertIssuerDN := oJson:StringOf("pkcs7.verify.signerInfo[i].cert.issuerDN")
    cCertDigestAlgOid := oJson:StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgOid")
    cCertDigestAlgName := oJson:StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgName")
    cContentType := oJson:StringOf("pkcs7.verify.signerInfo[i].contentType")
    cSigningTime := oJson:StringOf("pkcs7.verify.signerInfo[i].signingTime")
    cMessageDigest := oJson:StringOf("pkcs7.verify.signerInfo[i].messageDigest")
    cSigningAlgOid := oJson:StringOf("pkcs7.verify.signerInfo[i].signingAlgOid")
    cSignerDigest := oJson:StringOf("pkcs7.verify.signerInfo[i].signerDigest")
    j := 0
    nCount_j := oJson:SizeOfArray("pkcs7.verify.signerInfo[i].authAttr")
    DO WHILE j < nCount_j
        oJson:J := j
        cOid := oJson:StringOf("pkcs7.verify.signerInfo[i].authAttr[j].oid")
        cOidName := oJson:StringOf("pkcs7.verify.signerInfo[i].authAttr[j].oidName")
        cDer := oJson:StringOf("pkcs7.verify.signerInfo[i].authAttr[j].der")
        j := j + 1
    ENDDO
    i := i + 1
ENDDO

? "Success!"

oCrypt:destroy()
oJson:destroy()